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@article{DE_1987_23_11_a23, author = {O. Ya. Savchenko}, title = {On the eigenvalues of the {Sturm--Liouville} equation}, journal = {Differencialʹnye uravneni\^a}, pages = {2006--2008}, publisher = {mathdoc}, volume = {23}, number = {11}, year = {1987}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1987_23_11_a23/} }
O. Ya. Savchenko. On the eigenvalues of the Sturm--Liouville equation. Differencialʹnye uravneniâ, Tome 23 (1987) no. 11, pp. 2006-2008. http://geodesic.mathdoc.fr/item/DE_1987_23_11_a23/